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GOODWILL AND INTANGIBLE ASSETS - Narrative (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Mar. 28, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023 | Feb. 10, 2025
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill |  |  |  |  |  | $ 755,000
Goodwill impairment |  |  | $ 18,885,000 | $ 0 | $ 1,721,000 |
Impairment of definite-lived intangible assets | $ 37,510,000 | $ 92,397,000 | 129,907,000 |  |  |
Accumulated amortization, amount eliminated due to impairment |  |  | 77,927,000 |  |  |
Intangible asset amortization |  |  | $ 41,924,000 | $ 55,511,000 | $ 57,804,000 |
Intangible Assets, Amortization Period | Customer relationships |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Weighted Average Useful Life (Years) | 3 years |  | 3 years | 7 years |  |
Maximum | Customer relationships |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Weighted Average Useful Life (Years) | 14 years |  | 14 years |  |  |
Minimum | Customer relationships |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Weighted Average Useful Life (Years) | 6 years |  | 6 years |  |  |
Electrical |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Accumulated impairment loss | $ 5,645,000 |  | $ 5,645,000 |  |  |
Goodwill impairment |  |  | 0 |  |  |
Safety & Infrastructure |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Accumulated impairment loss | $ 61,885,000 |  | 61,885,000 |  |  |
Goodwill impairment |  |  | $ 18,885,000 |  |  |

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- Definition Finite-Lived Intangible Assets, Accumulated Amortization, Amount Eliminated Due To Impairment + References No definition available. + Details
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